Modloader custom items fix (#1369)

* Added item register and resolver for savegames

* Changed new item type example to register

* Fixed typings

src/js/game/base_item.js

@@ -15,7 +15,7 @@ export class BaseItem extends BasicSerializableObject {
         return "base_item";
     }
 
-    /** @returns {object} */
+    /** @returns {import("../savegame/serialization").Schema} */
     static getSchema() {
         return {};
     }

src/js/game/item_resolver.js

@@ -4,6 +4,8 @@ import { BooleanItem, BOOL_TRUE_SINGLETON, BOOL_FALSE_SINGLETON } from "./items/
 import { ShapeItem } from "./items/shape_item";
 import { ColorItem, COLOR_ITEM_SINGLETONS } from "./items/color_item";
 
+export const MODS_ADDITIONAL_ITEMS = {};
+
 /**
  * Resolves items so we share instances
  * @param {import("../savegame/savegame_serializer").GameRoot} root
@@ -13,6 +15,10 @@ export function itemResolverSingleton(root, data) {
     const itemType = data.$;
     const itemData = data.data;
 
+    if (MODS_ADDITIONAL_ITEMS[itemType]) {
+        return MODS_ADDITIONAL_ITEMS[itemType](itemData);
+    }
+
     switch (itemType) {
         case BooleanItem.getId(): {
             return itemData ? BOOL_TRUE_SINGLETON : BOOL_FALSE_SINGLETON;

src/js/mods/mod_interface.js

@@ -17,7 +17,7 @@ import { Loader } from "../core/loader";
 import { LANGUAGES } from "../languages";
 import { matchDataRecursive, T } from "../translations";
 import { gBuildingVariants, registerBuildingVariant } from "../game/building_codes";
-import { gComponentRegistry, gMetaBuildingRegistry } from "../core/global_registries";
+import { gComponentRegistry, gItemRegistry, gMetaBuildingRegistry } from "../core/global_registries";
 import { MODS_ADDITIONAL_SHAPE_MAP_WEIGHTS } from "../game/map_chunk";
 import { MODS_ADDITIONAL_SYSTEMS } from "../game/game_system_manager";
 import { MOD_CHUNK_DRAW_HOOKS } from "../game/map_chunk_view";
@@ -28,6 +28,8 @@ import { ModMetaBuilding } from "./mod_meta_building";
 import { BaseHUDPart } from "../game/hud/base_hud_part";
 import { Vector } from "../core/vector";
 import { GameRoot } from "../game/root";
+import { BaseItem } from "../game/base_item";
+import { MODS_ADDITIONAL_ITEMS } from "../game/item_resolver";
 
 /**
  * @typedef {{new(...args: any[]): any, prototype: any}} constructable
@@ -190,6 +192,15 @@ export class ModInterface {
         }
     }
 
+    /**
+     * @param {typeof BaseItem} item
+     * @param {(itemData: any) => BaseItem} resolver
+     */
+    registerItem(item, resolver) {
+        gItemRegistry.register(item);
+        MODS_ADDITIONAL_ITEMS[item.getId()] = resolver;
+    }
+
     /**
      *
      * @param {typeof Component} component

src/js/savegame/serialization.js

@@ -192,7 +192,7 @@ export class BasicSerializableObject {
         return schema;
     }
 
-    /** @returns {object} */
+    /** @returns {object | string | number} */
     serialize() {
         return serializeSchema(
             this,